Adam Dachis

Work used to include more physical activity. Now it mostly consists of death-accelerating sitting. Nevertheless, researchers found that weight gain issues haven't surfaced due to less physical activity each day. It turns out sitting at your desk for about eight hours doesn't affect obesity that much.

Yoni Freedhoff, writing for US News, explains:

Researchers analyzed the impact of physical activity on weight in a cross-sectional analysis of nearly half a million men and women in China. Participants provided researchers with self-reported amounts of daily physical activity that, in turn, were broken down to account for activities due to work, housework, active transportation and recreation. The results were rather underwhelming. Simply put, even huge amounts of additional physical activity failed to provide any dramatic benefits to weight. Without getting too bogged down in statistics, the researchers quantified physical activity in terms of something called "metabolic equivalent task hours" (MET-h/d). The average study participant was getting 22 of these a day. In terms of weight, the researchers found that a person needed to accumulate an additional 14 MET-h/d to affect a pound of body weight.

To put that number in a bit of perspective, you'd amass 3 MET-h/d by walking 3 miles in an hour. To put this all another way, to lose 10 pounds from physical activity would require you to be six times more active than the average person in this study; to lose 50 pounds would require you to be 30 times more active.